body, html {
    height: 100%;
    margin: 0;
}
.yemian1{
    width:1280px;
    height:960px;
    background-image: url("img/12.jpg");
    margin: 0 auto;
}
.container{
    text-align: center;


}
span{
    color:cornflowerblue;
    font-size: 10px;
}
.form-group{
    text-align: center;
}
.container1{
    text-align: center;
    width:1200px;
    height:700px;
    background-color: lightcyan;
    margin:0 auto;
}
.y2{
    width:1200px;
    height:700px;
    background-color:fuchsia;
    margin: 100px auto;
}

div {
    position: relative;
    height: 100%;
}

.container1{
    width: 100%;
    height: 100%;
    background-color: lightcyan;
    z-index: 1;
}

.y2{
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    background-color:fuchsia;
    z-index: 2;
}